Evaluation einer psychotherapeutischen Behandlungsmethode der chronischen Depression – das Cognitive Behavioral Analysis System of Psychotherapy (CBASP) als Gruppentherapie im stationären Setting – eine Pilotstudie

Background The Cognitive Behavioral Analysis System of Psychotherapy (CBASP), initially developed as an outpatient treatment for chronic depression (CD), has been adapted as an inpatient program including group therapy sessions. CBASP is based on a number of basic assumptions about chronic depression. One assumption is that chronically depressed patients are characterized by specific developmental deficits comparable to Piagetian preoperational structure, with deficits in interpersonal empathy, deficits in the awareness of one’s own stimulus character and ineffective social interactions. In this study the hypothesis is tested that multimodal treatment of chronically depressed patients involving CBASP group therapy exerts a positive effect on preoperational thinking, social problem solving, stimulus character, and empathic abilities. Methods CBASP group therapy was evaluated in an open-label multicenter study at the Universities of Bremen, Freiburg, Marburg and Munich. To test our hypothesis, a subsample of n = 20 patients included at the University of Marburg was investigated with a number of additional tools. Patients were included if the primary diagnosis was chronic depression, dysthymia or both (double depression) according to DSM IV. The study was approved by the local ethics committee. Group therapy was applied at an average dosage of 19.1 +/- 8.2 CBASP group sessions, each lasting 1.5 hours. Additional individual treatment sessions were applied in 80% of the patients. The following tools were applied before and after group therapy: Severity of depression using Becks Depression Inventory (BDI) and Hamilton Depression Rating Scale (HDRS), Quality of Life (WHOQOL-BREF), Acceptance of and satisfaction with group treatment, Lübeck Questionnaire for recording Preoperational Thinking (LQPT), Social Problem Solving Inventory (SPSI-R), Impact Message Inventory (IMI-R) and Reading the Mind in the Eyes Test (RMET-R). In a follow-up, BDI and Quality of Life were measured three months after completing the treatment. The main effects comparing the mean values from pre- and post-ratings were evaluated by repeated-measures ANOVAs. The predictive effect of changes under therapy for the 3-months outcomes were tested using regression analysis. Results Patients acceptance of CBASP group therapy was high (1.65 on a scale from 1 to 6 with 1 for highest acceptance). Comparing pre- and post-ratings there war a highly significant decrease of depressive symptoms (BDI -51.96%, HDRS -61.76%). Quality of life improved from 71.45 to 89.25 (+24.91%, p<.001). Preoperational thinking changed from 11.45 to 15.75 (+37.55%, p=.003), social problem solving from 39.85 to 55.30 (+38.77%, p<.001) and most of the IMI-R sub-scales changed significantly, for example the hostile-submissive scale that reduced from 3.01 to 2.46 (-22.35%, p=.002). Empathic abilities measured by RMET-R showed the smallest effect but still improved significantly from 22.85 to 25.60 (+12.03%, p=.007). Regression analysis revealed a predictive value of therapeutic changes in preoperational thinking, social problem solving and stimulus character on BDI and Quality of Life in the 3-months follow-up. Using hierarchical stepwise regression models, results showed changes in preoperational thinking to be the best predictor for BDI and Quality of Life in follow-up explaining more variance than any other factor could. Discussion These findings reveal that multimodal treatment of chronic depression involving CBASP group therapy exerts a therapeutic effect by modifying a number of specific deficits in chronically depressed patients. CBASP group therapy gained patients’ acceptance, led to a significant improvement of self-rated and observed-rated psychopathology, and significantly improved quality of life. Furthermore, core deficits in preoperational thinking, social problem-solving, stimulus character and empathic abilities improved over therapy. The improvements in preoperational thinking, social problem-solving, and stimulus character also predicted outcome after three months. The study is limited by the fact that this was an open-label design in a setting involving multimodal standard treatment. Nevertheless, core deficits of chronically depressed patients as identified by McCullough improved in a multimodal natural clinical setting including CBASP group therapy. In conclusion a larger, controlled study of specific therapeutic effects of CBASP group therapy is warranted.